The present invention refers to a cylindrical screening basket or basket strainer, and in particular to a screening basket for classifying fiber suspensions.
German patent DE-PS 34 00 423 describes a screening basket for classifying fiber suspensions which includes a perforated cylinder wall, with the screen openings being associated at the inside to a rotor and leading into grooves which are arranged at the suspension flow near surface of the screening basket and extend essentially transversely to the flow direction of the fiber suspension. A screening basket of this type desires to prevent an increase of the flow resistance of the screen; however, the attained sorting or classification remains unsatisfactory and thus the overall efficiency of the classification is also unsatisfactory. Same is true in case the strainer surface has a symmetrical, waved configuration.